What is 2(2.5b-9)+6b=-7 in solving multi step equations

8000 + 8800 + 8000 + 8 million + 80 trillion + another a katrillion equals

Astudent was asked to find the square of 7x+3. the student quickly wrote (7x+3)^3= 49x^2+9. identify the student's error and provide the correct answer.

3a + 5b - 7 = 0 a - 2b - 4 = 0 solve the system by the elimination method. check your work {(96/11, -5/11)} {(34/11, -5/11)} {(32/33, 5/11)}